That was the gap. confusable-vision is the tool I built to close it: render every confusable pair, measure the pixels, and put a number on what “visually confusable” actually means.
The “Knocking on Wood” Wikipedia page mentions Roud’s conclusion, and this claim of a 19th century origin has circulated online as the final say on the matter. If you go back to the original, though, Roud’s proposal actually ends on an ambivalent note: “Before this theory [of 19th century origins] can be finally accepted, however, an examination of the history of European forms of this custom would be advisable.”
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12:13, 27 февраля 2026Силовые структуры